Heretofore conveyor belts have been operated in generally straight paths without the ability to make transverse curves. In those few instances in which curved paths are followed, the curves have been very gradual so that pronounced differences in direction have required a curve extending over a great distance.
One prior art approach for permitting a belt to move in sharp transverse curves is described in U.S. Pat. No. 3,545,598. According to that disclosure, large corrugated edges are provided on each side of a relatively narrow central body portion. The entire conveyor belt is molded in a troughed configuration, with its edges bent up through the corrugations. In such an embodiment, the corrugations remain in a troughed configuration during the conveying of bulk material as well as during the return run of the belt. This requires a large height in which to operate a conveying system using such belt. Such a configuration achieves its objective of conveying bulk material around corners but suffers from deficiencies of relatively high vertical extent in which to operate, relatively high cost of fabrication and requiring relatively high operating power.
Flat molded conveyor belts troughable during the conveying of bulk material are disclosed in U.S. Pat. No. 3,679,044. In such configuration, however, no allowance is made for movement around sharp transverse curves.